Test prod



7 l 1.. 7 7 6, 2 m A w S S L 4 5 9 l nl 2 M A TEST PROD Filed April 30, 1952 Lloyd 5. Swain blij 1 0.@,1

IN V EN TOR.

Patented Apr. 27, 1954 UNIE Si" emu S iiNT QFFiCE TEST PR01) Lloyd S. Swain, Martinsville, Va., assigner of onehalf to Kathleen R. Swain, Martinsville, Va.

4 Claims.

This invention relates to a test prod and particularly to a prod to be attached to or detached from and rmly locked on to conductors and to electronic devices for testing or examining the same.

In the testing and maintenance of electronic devices such as radios, television sets and other electronic devices, it is necessary tc be able to determine the operative condition oi various circuits in the device. Also, it is frequently necessary to trace the circuits to determine at what portion of the circuit an accident has occurred.

The present invention provides a prod having an extremely small diameter and a nrin iast lock for attachment to conductors within the instrument. The prod comprises a cylindrical body member having an insulated coating thereon and a movable hook-lil e member for engaging a conduetor or wire in the set or instrument undergoing test and having lingers with which the hook acts to rrnly lock the prod on the wire. A conductor is connected. to the in insulated relation and the size and shape oi the prod is such that it may be hooked on to a Wire and left in position while the operator performs other tasks without the danger oi the prod jumping or being jarred loose from the connection.

it is accordingly an object oi this invention to provide an improved test prod.

Itis a further object of the invention to provide a test prod having a iirin engaging tip.

1t is a further object oi the invention to provide a test prod having a completely insulated structure.

It is a further object o the invention to provide a test prod having a protected connection to the prod.

It is still another object of the invention to provide a test prod which may be conveniently operated and left in position while the operator performs other functions.

Other objects and many of the attendant advantages of the present invention will be apparent from the following detailed description taken in conjunction with the accompany drawing, inwhich:

Figure l is a perspective view of the test prod;

Figure 2 is an enlarged longitudinal section showing the construction oi the prod taken substantially on the plane indicated by the line 2-2 of Figure 3;

Figure 3 is an enlarged cross section taken substantially on the plane indicated by the line 3--3 of Figure 2;

Figure 4 is an enlarged cross section taken sub 2 stantially on the plane indicated by the line 1 -4 of Figure 2; and

Figure 5 is an enlarged end view of the prod taken substantially on the plane indicated by the line 5 5 of Figure 2.

In the exemplary embodiment oi the invention an elongated nut-like base member it has rigidly attached to one end thereof a tubular body i2. The base member le is provided inten mediate the ends thereof with a collar ifi. The base iS is further provided with a longitudinally extending bore it which is substantially a continuation of the bore i8 of the tubular base i. O-ne end of the body l2 is provided with external threads 2d and adjacent the end thereof is provided with a seat 22 on which is mounted a spring seat 255. A substantially tubular handle Z is provided with internal threads 23 for meshing with the external threads 2li oi the base lil so that the end it of the handle 213 can be screwed into iirm engagement with the upstanding collar lli of the base member lil.

The handle it is provided at the far end thereor" with a guide sleeve 32 which has a square or other non-circular guide channel il therein. A connector block 35 is slidably mounted in the guide sleeve 32 for sliding movement in the channel 317i. The connector block 35 is provided with an axial bore B in which is mounted a wire-like rod it. The rod il@ extends axially through the handle 2d, the oase it and the body i2 to extend from the remote end of the body it where it is provided with a hook-like member d2, the rod All being nrinly secured to the connector block 35 bylineans of a set screw dfi. The inner end of the connector block 36 is provided with a spring seat d5 and a compression spring #lil is mounted between the seats 24 and it to resiliently urge the connecting block 36 outwardly from the handle 25.

The outermost end ci the body i2 has connected thereto a pair oi fingers 5d and 52 which are firmly secured to the outer surface adjacent the end of the body by any suitable means, such as welding, brazing or soldering and they extend in dii/erging outwardly flaring relation to provide a tf-shaped groove 54 and to which the hook member 62 may be engaged. rlfhe spring de by urging the connecting bar 35 outwardly will maintain the hook S2 in rm engagement with anything such as a conductor lili which has been selectively engaged by the hook d2.

An insulating coating 'it is applied to the external portion oi the body 2t and extends upwardly over the portion of the fingers 50 .and

3 52 which are connected to the end of the body l2 and also extends upwardly over that portion of the base IU which is connected to the body I2 and extends outwardly of the body IG to the annular collar l 4 with which it is substantially iiush.

The connector block 36 is provided with a transverse opening 64 through which the end of a conductor 66 may be extended. The connector block 36 is also provided with a longitudinal internally threaded bore 68 in which is threadedly engaged a lock screw '19. The lock screw l'll has a non-circular head 12 on which is molded or otherwise connected an insulating thumb screw i4. The conductor 66 is secured in rm relation in the passage 64 by turning the nut 'I4 to put the set screw lil in iirm engagement with the conductor 66.

An actuating member 'l5 has a head 18 which is molded or otherwise connected to the end of the connecting block 35 and has a substantially tubular sleeve 80 mounted in sliding telescopic relation with the exterior surface of the handle 25. A reinforcing sleeve 82 extends laterally from one side of the telescoping sleeve 80 and the conductor 66 extends thereto to be reinforced adjacent to its connection to the connector block 42.

An annular disk-like projection 86 is provided intermediate the ends of the handle 2S to provide a rm finger-grip for the operator on the handle of the prod.

In the operation and use of the device the conductor 66 is firmly connected to the connecting block Sii which is, in turn, firmly connected to the rod fifi having the hook 12. The actuating member 'It is depressed between the thumb and finger' of the operator so that the hook 42 is free to extend outwardly from the end of the body E2 and may be engaged over any of the conductors in the electronic device. By releasing the pressure between the actuating member 1B and the annular collar 86 the hook 42 will be allowed to move inwardly under the tension of the spring 48 to lock the selected conductor 55 nrmly between the hook and the fingers 5l] and 52 so that the prod will be in rm locking engagement with the conductor and may be allowed to remain in position while the operator performs other` tasks without there being any danger of the prod being jarred loose or otherwise accidentally removed from the conductor 56.

It will thus be seen that there has been provided an effective test prod which may be readily connected with various portions of the equipment under test and left without danger of being jarred or accidentally removed therefrom.

A preferred embodiment of the invention has been shown, and described according to the best present understanding thereof. It will be apparent to those skilled in the art that changes and modifications may be made therein without departing from the true spirit of the invention.

Having described the invention, what is claimed as new is:

l. A test probe comprising an elongated tubular body, a pair of outwardly flaring diverging fingers secured adjacent one end of the body, a wire-like rod slidably mounted in said body, a portion of said rod protruding from said body, a hook on said protruding portion, said hook extending over the outer end of said body and being received between said fingers.

2. A test prod comprising an elongated tubular body, a pair of outwardly daring diverging fingers secured adjacent one end of the body and extending radially beyond the end of the body, a wire-like rod slidably mounted in said body, a portion of said rod protruding from said body, a hook on said protruding portion, said hook extending beyond the outer end of .said body and being received between said fingers, and an insulating coating on said tubular body including the base of said diverging fingers.

3. A test prod comprising an elongated nutlike base, a tubular body rigidly secured on said base, outwardly flaring diverging iingers secured to said body and extending beyond the end thereof, an insulating surface applied to said body and a. portion of said base, a rod slidably mounted in said body, a hook on the end of said rod,r

said hooi: extending laterally over the end of said body cooperating with said fingers.

4. In a test probe having an elongated tubular body and a spring biased hook rod slidably mounted in said body, a selector terminal comprising a pair of diverging outwardly flaring fingers rigidly mounted on said tubular body, said ngers providing an outwardly daring V-shaped groove, a hook end on said hook rod, said hook end extending laterally over the end of said body and being received between said fingers.

References Cited in the ile of this patent UNITED STATES PATENTS Number Name Date 2,094,392 Winslow Sept. 28, 1937 2,516,657 Spendlove July 25, 1950 2,529,270 Webster Nov. '7, 1950 

